use std::any::Any;
use std::mem;

use runtime::{Class, Object, Imp, Sel};
use super::{Message, MessageArguments, MessageError, Super};

extern {
    fn objc_msg_lookup(receiver: *mut Object, op: Sel) -> Imp;
    fn objc_msg_lookup_super(sup: *const Super, sel: Sel) -> Imp;
}

pub unsafe fn send_unverified<T, A, R>(obj: *const T, sel: Sel, args: A)
        -> Result<R, MessageError>
        where T: Message, A: MessageArguments, R: Any {
    if obj.is_null() {
        return mem::zeroed();
    }

    let receiver = obj as *mut T as *mut Object;
    let msg_send_fn = objc_msg_lookup(receiver, sel);
    objc_try!({
        A::invoke(msg_send_fn, receiver, sel, args)
    })
}

pub unsafe fn send_super_unverified<T, A, R>(obj: *const T, superclass: &Class,
        sel: Sel, args: A) -> Result<R, MessageError>
        where T: Message, A: MessageArguments, R: Any {
    let receiver = obj as *mut T as *mut Object;
    let sup = Super { receiver: receiver, superclass: superclass };
    let msg_send_fn = objc_msg_lookup_super(&sup, sel);
    objc_try!({
        A::invoke(msg_send_fn, receiver, sel, args)
    })
}